scholarly journals Morphology of endothelial cells from different regions of the cornea of dogs

2018 ◽  
Vol 48 (10) ◽  
Author(s):  
Paula Stieven Hünning ◽  
Maria Cristina Caldart de Andrade ◽  
André Carissimi ◽  
João Pigatto
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Morphology ◽  
Corneal Endothelium ◽  
Central Area ◽  
Alizarin Red ◽  
Central Cornea ◽  
Significant Difference ◽  
Peripheral Areas ◽  
Healthy Eyes

ABSTRACT: The aim of this study was to evaluate the morphology of endothelial cells from different areas of the cornea of dogs. Twenty healthy eyes from 10 dogs, females or males, of different ages were studied. Corneal endothelium morphology of superior, inferior, central, nasal and temporal areas was assessed by 0.2% alizarin red staining using an optic microscope. One hundred endothelial cells from each corneal area were analyzed. In all areas of the cornea studied were found endothelial cells with four sides, five sides, six sides and seven sides. There was no significant difference regarding endothelial cell morphology in all corneal regions evaluated. Thus, the morphology of the central cornea area represents the entire endothelial mosaic and may be applied to peripheral areas. Therefore, analysis of the central area is sufficient to estimate the shape of endothelial cells of peripheral areas of healthy dog corneas.

Effects of Steady Spatial Wall Shear Stress Gradients on Endothelial Cell Morphology in Three-Dimensional Models

2007 ◽  
Author(s):  
Leonie Rouleau ◽  
Monica Farcas ◽  
Jean-Claude Tardif ◽  
Rosaire Mongrain ◽  
Richard Leask
Keyword(s):  
Endothelial Cells ◽  
Shear Stress ◽  
Endothelial Cell ◽  
Wall Shear Stress ◽  
Cell Morphology ◽  
Flow Direction ◽  
Stress Gradient ◽  
Spatial Gradient ◽  
Stress Gradients ◽  
Wall Shear

Endothelial cell (EC) dysfunction has been linked to atherosclerosis through their response to hemodynamic forces. Flow in stenotic vessels creates complex spatial gradients in wall shear stress. In vitro studies examining the effect of shear stress on endothelial cells have used unrealistic and simplified models, which cannot reproduce physiological conditions. The objective of this study was to expose endothelial cells to the complex shear shear pattern created by an asymmetric stenosis. Endothelial cells were grown and exposed for different times to physiological steady flow in straight dynamic controls and in idealized asymmetric stenosis models. Cells subjected to 1D flow aligned with flow direction and had a spindle-like shape when compared to static controls. Endothelial cell morphology was noticeable different in the regions with a spatial gradient in wall shear stress, being more randomly oriented and of cobblestone shape. This occurred despite the presence of an increased magnitude in shear stress. No other study to date has described this morphology in the presence of a positive wall shear stress gradient or gradient of significant shear magnitude. This technique provides a more realistic model to study endothelial cell response to spatial and temporal shear stress gradients that are present in vivo and is an important advancement towards a better understanding of the mechanisms involved in coronary artery disease.

scholarly journals The Effect of Phacoemulsification on Corneal Endothelial Cells Morphology and Thickness

2020 ◽  
Vol 36 (4) ◽  
Author(s):  
Abd Elaziz Mohamed Elmadina ◽  
Raghda Faisal Abdelfatah ◽  
Saif Hassan Alrasheed ◽  
Mustafa Abdu ◽  
Manzoor Ahmad Qureshi
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Density ◽  
Corneal Endothelium ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Endothelial Cell Density ◽  
P Value ◽  
Corneal Endothelial Cells ◽  
Before And After

Purpose:  To compare the corneal endothelial cells morphology and central corneal thickness (CCT) before and after phacoemulsification in Sudanese population. Place and Duration of Study:  Al-Neelain eye hospital, Khartoum, Sudan, from January 2018 to May 2018. Study Design:  Observational longitudinal study. Methods:  One hundred and forty eyes of 140 patients with immature senile cataract were selected by convenient sampling. The age ranged from 40 to 85 years. The patients underwent complete ocular examination including morphology of corneal endothelial cells and CCT using computerized non-contact specular microscope. Inclusion criteria for the study was eyes with normal corneal endothelial cells and cell density more than 1000 cells/mm2. We excluded patients with ocular or systemic diseases, previous history of intraocular surgery, refractive surgery or trauma as well as contact lenses wear. The patients underwent phacoemulsification by a single surgeon. The examination parameters were repeated one month after surgery. Descriptive and comparative statistical analyses were performed using SPSS for Windows Version 21.0. Results:  There was significant reduction in mean endothelial cells density after phacoemulsification compared to baseline with p < 0.001. There was also significant post-operative reduction in mean endothelial cells number as compared to baseline (P value < 0.001). Mean endothelial cells hexagonality was reduced after surgery with P value of 0.003. No significant difference was found between mean coefficient variation of endothelial cells size before and after phacoemulsification (P = 0.55). Central corneal thickness showed significant increase post-operatively, P = 0.003. Conclusion:  Phacoemulsification causes significant damage to corneal endothelium cells, including decrease in corneal endothelial cell density, hexagonality and cell number. Key Words:  Corneal endothelium, Endothelial cell density, Central corneal thickness, Phacoemulsification.

scholarly journals Morphology of Endothelial Cells from Different Regions of the Swine Cornea

2019 ◽  
Vol 47 (1) ◽  
Author(s):  
Lídia Luzia Clerot ◽  
Paula Stieven Hünning ◽  
Marcelle Bettio ◽  
Marcela Torikachvili ◽  
Michelle Beck Petersen ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Optical Microscopy ◽  
Repeated Measures ◽  
Corneal Endothelium ◽  
Anterior Segment ◽  
Optical Microscope ◽  
Specular Microscopy ◽  
Microscope Slide ◽  
Large White ◽  
Alizarin Red

Background: The corneal endothelium is a monolayer of polygonal cells which constitute the last layer of the cornea. The integrity of this layer is critical to cornea transparency. The characterization of normal corneal endothelial morphology is important not only to clinical evaluation but also to selection of areas of the cornea with better quality to be employed as donor tissue. The aim of the present study was to evaluate the morphology of endothelial cells from different regions of the swine cornea after alizarin red staining using optical microscopy.Materials, Methods & Results: Twenty-four healthy eyes from 12 swine Large White breed, with 14-month-old, males or females obtained from a licensed Brazilian commercial slaughterhouse were studied. Immediately after humane slaughter, the eyes were enucleated and submitted to ophthalmic examination. Eyes with signs of diseases of the anterior segment were excluded. The cornea, with 3 mm of the sclera, was removed and placed on a glass microscope slide with the endothelial side up. Four radial incisions were made in the periphery of the cornea to better accommodate the cornea on the microscope slide. Alizarin red was diluted in isotonic solution (0.2 g/100 mL) and the pH was adjusted to 4.2 with hydrochloric acid. Three drops of alizarin red were placed on the corneal endothelium. After 90 s, the dye was removed from the cornea with balanced saline solution. The corneal endothelium was examined and photographed using an optical microscope. All evaluations were performed by the same investigator. Photomicrographs were taken of central, superior, inferior, nasal and temporal corneal areas. Parameter studied included endothelial cell morphology. For the statistical analysis, was employed the ANOVA variance test (repeated measures). Differences were considered statistically significant at P < 0.05. Normal endothelium cells were mainly hexagonal (83.7%), pentagonal (7.45%) and heptagonal (8.8%), with a minimal number of cells of other shapes present. There were no significant statistical differences in the proportion of the morphology and the different regions of the cornea (P = 0.31).Discussion: Different techniques are available for the analysis of corneal endothelium, including mainly scanning electron microscopy, specular microscopy and optical microscopy. The analysis of the morphology of corneal endothelium with an optic microscope after staining with alizarin red has been described as an effective, rapid and cost-efficient method, since this dye blends the borated cells, allowing identification. In the present study, using optical microscopy and coloration with alizarin red it was possible to explore and to obtain images of the swine endothelium of all regions of the cornea.  The analysis of the cellular morphology or the percentage of hexagonal cells are among the main parameters used to evaluate the health of the corneal endothelium. In this study, the endothelium had the predominance of the hexagonal shape in all regions studied. In swine, there are no studies evaluating the shape of the endothelial cells in the five different regions of the cornea. This study has demonstrated that the parameters evaluated in swine did not differ significantly between the various places of the cornea.

scholarly journals EPAC2 acts as a negative regulator in Matrigel-driven tubulogenesis of human microvascular endothelial cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Takayuki Ikeda ◽  
Yoshino Yoshitake ◽  
Yasuo Yoshitomi ◽  
Hidehito Saito-Takatsuji ◽  
Yasuhito Ishigaki ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Morphology ◽  
Molecular Mechanisms ◽  
Network Formation ◽  
Tissue Growth ◽  
Negative Regulator ◽  
Endothelial Cell Migration ◽  
Microvascular Endothelial Cells ◽  
Microvascular Endothelial

AbstractAngiogenesis is physiologically essential for embryogenesis and development and reinitiated in adult animals during tissue growth and repair. Forming new vessels from the walls of existing vessels occurs as a multistep process coordinated by sprouting, branching, and a new lumenized network formation. However, little is known regarding the molecular mechanisms that form new tubular structures, especially molecules regulating the proper network density of newly formed capillaries. This study conducted microarray analyses in human primary microvascular endothelial cells (HMVECs) plated on Matrigel. The RAPGEF4 gene that encodes exchange proteins directly activated by cAMP 2 (EPAC2) proteins was increased in Matrigel-driven tubulogenesis. Tube formation was suppressed by the overexpression of EPAC2 and enhanced by EPAC2 knockdown in endothelial cells. Endothelial cell morphology was changed to round cell morphology by EPAC2 overexpression, while EPAC2 knockdown showed an elongated cell shape with filopodia-like protrusions. Furthermore, increased EPAC2 inhibited endothelial cell migration, and ablation of EPAC2 inversely enhanced cell mobility. These results suggest that EPAC2 affects the morphology and migration of microvascular endothelial cells and is involved in the termination and proper network formation of vascular tubes.

scholarly journals Comparison of the Changes in Corneal Endothelial Cells after Pars Plana and Anterior Chamber Ahmed Valve Implant

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Ji Won Seo ◽  
Jong Yeon Lee ◽  
Dong Heun Nam ◽  
Dae Yeong Lee
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Anterior Chamber ◽  
Cell Damage ◽  
Corneal Endothelial Cells ◽  
Refractory Glaucoma ◽  
Endothelial Cell Damage ◽  
Significant Difference ◽  
Pars Plana

Purpose. To compare the changes in corneal endothelial cells after pars plana Ahmed glaucoma valve (AGV) implantation with those after the anterior chamber AGV implantation for refractory glaucoma.Methods. The medical records of 18 eyes with pars plana implantation of AGV (ppAGV) were reviewed retrospectively and were compared with 18 eyes with the anterior chamber AGV (acAGV) implant. The preoperative and postoperative endothelial cells, intraocular pressure (IOP), and postoperative complications during the follow-up in both groups were compared.Results. The average follow-up was 18 months. The postoperative endothelial cells in the ppAGV and acAGV groups were 2044 ± 303 and 1904 ± 324, respectively(P=0.25). The average percentage decrease in the endothelial cells in the ppAGV and acAGV groups at 18 months was 12.5% and 18.4%, respectively, and showed significant difference between the 2 groups(P=0.01). No difference in IOP control and the number of postoperative glaucoma medications was observed between the 2 groups.Conclusions. Endothelial cell damage in the ppAGV group for refractory glaucoma appeared to be lower than that in the acAGV group. Therefore, pars plana implantation of AGV may be preferred as it may have lower level of endothelial cell damage while maintaining similar level of IOP control.

Comparison between the protective effect of Ophthalmic Viscoelastics on the corneal endothelium in phacoemulsification

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
S M A Saleh ◽  
R M F Elghazawy ◽  
A I Elawamry ◽  
R G Zaki
Keyword(s):  
Visual Acuity ◽  
Endothelial Cell ◽  
Protective Effect ◽  
Cell Count ◽  
Corneal Endothelium ◽  
Hydroxypropyl Methylcellulose ◽  
Methyl Cellulose ◽  
Endothelial Cell Count ◽  
Significant Difference ◽  
Group 2

Abstract Background Phacoemulsification is one of the most common surgical interventions done worldwide; the ultrasound power used to emulsify and remove the cataractous lens is hazardous to corneal endothelium and can lead to permenant damage. Thats why ophthalmic viscoelastics have been developed and used to protect the corneal endothelium and ensure safety of intraocualr surgeries. Objective To study the effect of different concentrations of methyl cellulose on the corneal endothelium during phacoemulsification using specular microscopy. Patients and Methods Sixty patients with Immature Senile Cataract (IMSC) are equally distributed into two groups according to the concentration of Hydroxypropyl Methylcellulose (HPMC) used during phacoemulsification. In the first group HPMC 2% was used and in the second group HPMC 2.4% was used. Preoperative and one month postoperative examination was done including visual acuity testing, slit lamp examination using Topcon SL-3C, intraocular pressure measurement using Goldmann Applanation Tonometer (GAT), fundus examination, corneal edndothelium assessment by Tomey Specular Microscope EM-3000. Results Preoperatively, no significant difference was observed in age, sex, visual acuity, introcular pressure and endothelial cell count among the two groups. Postoperatively, the two groups had a significant decrease in endothelial cell count, but the decrease was less in group 2 using Methyl cellulose 2.4% (13.494%) than in group 1 using Methyl cellulose 2% (14.515%).There was an equal and significant increase in visual acuity in the two groups. Discussion Many studies have been done to compare the efficacy of different viscoelastics (OVDs) in the protection of corneal endothelium during phacoemulsification. In our study we compared the protective effect of two different concentrations of HydroxyPropyl MethylCellulose (2% &2.4%) on the corneal endothelium during phacoemulsification. We compared the demographic data as regarding age and sex of the patients in the two groups, also we compared the preoperative endothelial cell count in the two groups using Specualr Microscopy and the result showed no significant difference between the 2 groups. The endothelial cell loss was comparable in the 2 groups, in group 1 it was 362.267 ± 52.020 (14.515 % ± 1.458) and in group 2 it was 335.667 ± 21.170 (13.494% ±0.667) with slightly better protection in the second group. So these results shows that HPMC 2.4% gives better protection than HPMC 2% on corneal endothelium during phacoemulsification on terms of the postoperative endothelial cell count and the endothelial loss after phacoemulsification. Many studies have been done to compare the efficacy and the protective effect of different viscoelastics during phacoemulsification for example the studies done by Miller et al, Maar et al, Vajpayee et al and Storr-Paulsen et al, these studies showed results similar to our study as regards the protective effect of methyl cellulose with its different concentrations on the corneal endothelium during phacoemulsification, so both concentrations (2% and 2.4%) can be used safely and effectively in phacoemulsification to decrease the endothelial loss and ensure patients safety. Conclusion Methyl cellulose 2.4% and Methyl cellulose 2% were comparable in their ability to protect the corneal endothelium during phacoemulsification, in general both viscoelastics can be efficiently and safely used in performing phacoemulsification.

Vascular Endothelial Morphology as an Indicator of the Pattern of Blood Flow

1981 ◽  
Vol 103 (3) ◽  
pp. 172-176 ◽  
Author(s):  
R. M. Nerem ◽  
M. J. Levesque ◽  
J. F. Cornhill
Keyword(s):  
Endothelial Cells ◽  
Blood Flow ◽  
Endothelial Cell ◽  
Cell Morphology ◽  
Flow Direction ◽  
Rabbit Aorta ◽  
Shape Index ◽  
En Face ◽  
Length Width ◽  
Branch Vessel

A quantitative study of the en face size and shape of endothelial cells from aortic intercostal ostia has been carried out in rabbits. Photomicrographs were taken from vascular casts of the rabbit aorta and the endothelial cell outlines were analyzed quantitatively using a digitizer and digital computer. The morphology of the endothelial cells was described using 8 calculated parameters (area, perimeter, length, width, angle of orientation, width: length ratio, axis-intersection ratio and shape index). Marked changes in cell morphology were found in the regions proximal and distal to ostia as well as around flow dividers. Cells on the aorta are aligned with the flow direction, and the endothelial cells within the ostia have an angle of orientation of approximately 45 deg to the axis of the vessel. The results obtained to date suggest that endothelial cell morphology and orientation around a branch vessel may be a natural marker or indicator of the detailed features of blood flow.

Effects of magnesium on nitric oxide synthase activity in endothelial cells

1995 ◽  
Vol 269 (3) ◽  
pp. C612-C618 ◽  
Author(s):  
A. B. Howard ◽  
R. W. Alexander ◽  
W. R. Taylor
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Endothelial Cell ◽  
Nitric Oxide Synthase ◽  
Magnesium Concentration ◽  
Control Activity ◽  
Intracellular Magnesium ◽  
Significant Difference ◽  
No Release ◽  
Oxide Synthase

Magnesium modulates endothelium-dependent vasodilation in intact blood vessels. Therefore, the effects of magnesium on nitric oxide (NO) release by isolated endothelial cells and nitric oxide synthase (NOS) activity in endothelial cell homogenates were studied. Unstimulated and bradykinin-stimulated NO release by porcine aortic endothelial cell (PAEC) monolayers were unaffected by 30 min of exposure to magnesium concentrations varying from 0.010 to 10.0 mM. In contrast, when A-23187-stimulated cells were exposed to 0.01, 3.16, and 10.0 mM MgCl2, NO release was decreased by 11.3 +/- 1.8, 11.7 +/- 3.0, and 20.3 +/- 7.2%, respectively, compared with cells exposed to 1.0 mM MgCl2 (P < 0.01). These data suggested that a change in the intracellular magnesium concentration had an effect on NO release, in contrast to a change in the extracellular concentration, which did not have an effect. To further assess this possibility, crude NOS extracts were prepared from PAEC and exposed to MgCl2. NOS activity was measured via the conversion of L-[3H]arginine to L-[3H]citrulline. Increasing the concentration of MgCl2 by 1.0, 3.16, and 10.0 mM caused a 16.0 +/- 6.8, 17.1 +/- 1.7, and 38.6 +/- 5.3% decrease in citrulline formation, respectively (P < 0.05), suggesting a direct inhibition of NOS by MgCl2. No significant difference in the degree of inhibition of NOS activity was found between MgSO4 and MgCl2, thus ruling out a nonspecific chloride effect. In addition, increasing the concentration of NaCl to 15 mM had no effect on NOS activity, ruling out a nonspecific osmotic effect [101.6 +/- 10.5% of control activity, P = not significant (NS)].(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Morphological analysis of the corneal endothelium in eyes of dogs using specular microscopy

2008 ◽  
Vol 28 (9) ◽  
pp. 427-430 ◽  
Author(s):  
João A.T. Pigatto ◽  
Cristine Cerva ◽  
Cesar D. Freire ◽  
Fernando C. Abib ◽  
Luciano P. Bellini ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Corneal Endothelium ◽  
Morphological Analysis ◽  
Specular Microscopy ◽  
Human Cornea ◽  
Corneal Endothelial Cells ◽  
Peripheral Cornea ◽  
Specular Microscope ◽  
Healthy Eyes ◽  
Number Of Cells

Both healthy eyes of 10 six-year-old male and female mongrel dogs were studied. With a contact specular microscope the corneal endothelium was examined. Endothelial cells were analyzed in the central and peripheral cornea. Morphological analysis with regard to polymegathism and pleomorphism was performed. Three images of each region with at least 100 cells were obtained. The analysis showed that polygonal cells formed a mosaic-like pattern uniform in size and shape. The predominant number of cells was hexagonal. The polymegathism index was 0.22. The study demonstrates that the morphology of the normal corneal endothelial cells of dogs is similar to that found in the human cornea.

The state of corneal endothelial cells in the dynamics of surgical treatment of age-related and diabetic cataracts

2021 ◽  
pp. 47-50
Author(s):  
S.Y. Totskova ◽  
◽  
A.E. Babushkin ◽  
Е.M. Garipova ◽  
◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Surgical Treatment ◽  
Corneal Endothelium ◽  
Corneal Endothelial Cell ◽  
Corneal Endothelial Cells ◽  
Diabetic Cataract ◽  
Age Related ◽  
Corneal Endothelial Cell Density

Purpose. To assess the state of the corneal endothelium in patients with diabetic and immature age - related cataracts before and in the long term after phacoemulsification. Material and methods. There were 25 patients (43 eyes) under observation in total. The average age is 66.4±10.1 years. There were 12 men and 13 women among the surveyed. The average time after cataract phacoemulsification was 5.6±1.7 years. There were 2 groups of patients: group I (main) included 10 patients (16 eyes) with diabetic cataract, group 2 (control) consisted of 15 patients (27 eyes) with immature senile cataract (ISC) without diabetes. Before and after phacoemulsification the central corneal thickness (CCT), as well as polymegatism, pleomorphism, and corneal endothelial cell density (ECD) were studied using an EM-2000 endothelial microscope (Nidek, Japan). Results. In the long-term period after cataract phacoemulsification there was decreasing trend in the corneal endothelial cell density (ECD) as in patients operated on for immature senile and especially diabetic cataracts (by 1.5 times). The initial data of ECD in patients with diabetic cataract in comparison with ISC were lower although not significantly. There was also a decreasing trend in the percentage of hexaganality and the number of normal endothelial cells, as well as an increase in the coefficient of their polymegatism after phacoemulsification in patients with DM in comparison with patients without it. Conclusion. The study showed that phacoemulsification of diabetic cataracts is associated with more pronounced damage to the corneal endothelium when compared with the ISC group. During phacoemulsification with IOL implantation, especially in patients with diabetic cataracts, you should pay attention to the initially possible smaller ECD and take this circumstance into account when performing phacoemulsification. Key words: diabetic cataract, surgical treatment, phacoemulsification, endothelial microscopy, corneal endothelial cells.

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